Retrieving core barrel



H. PENNINGTON RETRIEVING CORE BARREL Jan. 2.4-, 1939.

Original Filed July le, 1929 duo: mui..

Patented 311.24, 1939 PATENT OFFICE RETRIEVING CORE BARREL Harry Pennington, San Antonio, Tex.

Application July 16, 1929, serial No. 318,613

, Renewed December 14, 1933 42 Claims.

My invention 4relates to core barrels for use with core drills employed in deep well drilling where a sample of the formation being drilled is contemplated.

'5 In well drilling for oil, gas, sulphur` and the like it is desirable to obtain samples of the formation being drilled wherever there is reason to believev that a producing.stratum has been encountered. In fact it is becoming quite common to obtain a complete log of the formation encountered in the well from the top to the bottom thereof and the use of core drills whereby samples of the formation may be obtained is becoming more and more common.

Thev common type of core drill employs a tubular bit having acentral passage thru which a core may be projected upwardly into the core barrel as the drill advances. When the sample is to be brought -to the surface for inspection it is necessary to withdraw the drill with the core barrel to the surface. In deep wells particularly this is a long and laborious operation, necessitating removing the drill stem section by section to bring the drill to the surface so that the core may be -removed. Each time a core is to be obtained this process must be repeated.

. It is an object of my invention to provide a core barrel which may be employed with any ordinary type of coredrill and/to so construct and arrange the drill and core barrel that the core barrel with-the sample therein may be removed while the drill is in position in the bottom of the well and without necessitating the withdrawal of the drill.

with the usual type of core bit, which may be introduced into position in the core drill to obtain a sample therein, and held in place while the sample is being taken by hydraulic pressure. I also contemplate the removal of the core barrel with its sampleA therein to the surface by hydraulic means without the necessity of any other apparatus to be inserted into the well.

I also desire to provide means in connection when the core barrel has been properly seated ,and is ready for operation.

The invention resides in the particular con-V struction and arrangement of the core barrel and its connection with the drill and drill stem and a fuller understanding thereof will be obtained thru the more detailed specication which follows:

Referring to the drawing herewith, l

55 Fig. 1 is a central longitudinal section thru the I aim to provide a core barrel to'be employed with the corebarrel to indicate to thedriller (Cl. Z55-72) upper enc' of the well and of my ldevice inserted therein, they upper end thereof being shown in this view.

Fig. 2 is a similar section showing the lower end of the well with my apparatus therein. 5 In the drawing I have shown the lower end of the drill stem at I in Fig. 2, said drill stem being connected at its lower end to the core bit 2. The bit shown herewith is an ordinary type of scraping drill having a body 3, with laterally extending 10 blades Il to cut theclearance at the bottom or the hole. Thedrill head 3 has a circular opening 5 at the lower end to receive the core. Above this opening the central passage thru the head of the bit is enlarged somewhat to provide a tap- 15 ered seat or shoulder at `6 toreceive the lower end of the core barrel 1. Above the socket provided to receive the core barrel the inner portion of the head is beveled outwardly at 8 and longitudinal passages 9 thru the head allow for the 20 discharge of ushing fluid onto the forward ends of the cutting blades.

The lowersection I of the drill stem has, at a point suitably spaced from the lower end, a' coupling I0. An inner bushing Il is screwed 25 within the meeting ends of the pipe at this point to provide a somewhat constricted passage I2 of suiiicient size to make a close sliding contact with the core barrel which is adapted to pass therethru. The upper and lower ends of the bushing 30 II are tapered, as shown at I3, to guide the parts of the core barrel into the passage I2.

Above the coupling I0 the sections of the drill stem are provided at intervals with tool joints I4, said tool joints having the passage I5 therethru 35 of. sufficient size to allow the movement therethru of the core barrel. The upper end ofthe drill stem is` of ordinary construction but I contemplate in the taking of the core that I may mount upon the drill stem at its upper end a 40 special coupling member or bushing I5', adapted to fit within the tapered seat I6 in the casing head I1. It is to be understood that this coupling member will have to be mounted upon the drill stem when the core barrel is to be removed. In place of thisl particular coupling a special packing member may be inserted between the drill stem and the casing head to form therewith a iluid tight closure about the drill stem as is necessary in the removing of the core barrel, as will be later noted.

The core barrel comprises a lower section I8,v which is formed with adownwardly tapered bevel at I9 to t against the shoulder 6 in the head of the bit. This core barrel will be of suicient length to receive a sample of the desired length barrel is provided with an head 22.

in the use of the device. The upper end of l or by means of set screws or the like. Said partition has a plurality of longitudinal openings 24 therein to allow the passage of iuid.` The saidopenings are normally closed at their upper ends by means of an upwardly opening valve 25. Said valve has a downwardly extending stem 26 which the bushing n.

serves to guide the valve and to limit its upward movement. spring-21, which bears against the lower end of the head 22 and tends to iiange 2| against the flange 20.

The head 22 is a tubular member and between its ends is formed an enlarged portion 28, the outer periphery of which is cylindrical at 29 and adapted to t closely within the passage I2 thru Above the enlarged portion the with radial openings 30, leading passage 3| in the head, so as to allow an outlet for liquid therethru. The upper end of the head is enlarged and threaded to engage with the upper section 32 of the core barrel. Said upper section 32 of the barrelis extended a suiiicient distance to reach from one tool joint to another within the drill stem, it being desired that some portion. of the outer surface of the core head is provided to the central -barrel shall be extending thru one tool joint in the drill stem at all times.

The upper end of the extension 32 is closed by a guide plug,33, which is tapered upwardly and has longitudinal passages 34 therein for fluid. These passages are closed at the lower end of Said plug within the barrel by a valve plate 35held normally in closed position by a spring 36 upon a stationary stem 31, secured within the plug.

I contemplate the use with the core barrel I8 of a core-engaging member 3sat thelower end thereof and this core engaging member may be of any desired construction. I have shown a plurality of spring arms mounted in recesses on the inner sur.- face of the core barrel and adapted to move inwardly at the upper ends to engage the core. These core-engaging members serve also to support a pilot or guide member 38 while the device is going into the hole. Said pilot or guide may be a plug of wood or other light material tapered at the lower end, the upper end being cylindrical and adapted to engage with the spring arms 38 of the core-engaging device and be thus held in position, vpreventing the entrance of mud or other foreign material to the core barrel, while it is being inserted into the hole. Said plug may be moved upwardly ahead of the core, however, thru the pressure oi' the core as it is formed.

In the operation of the device the core drill may be operated without the use of the core barrel, if desired. ever, the core bit will be raised from the bottom ofthe hole and flushed free of any material which may be therein during the drilling of the hole.

. After being thus cleared of material and the bottom of thev hole being washed clean the bit will be lowered to position at the bottom of the hole and the core vbarrel assembled as shown in the drawing willbe inserted into the upper end of the drill stem and the flushing iluid will thenbe pumped downwardly to force thecore barrel into position at the bottom of the hole. As the core barrel moves downwardly thru the drill stem the spring 21 will hold the core barrel I8 andthe head Above the valve is a compressionnormally hold the against the bottom and its load will thus be forced When it is desired to take a core, how-- the'core barrel into i the fact that the circulation will be momentarily build up the pressure 22 in extended position with the ilanges 20 and 2| in engagement. When the device reaches the bottom of the hole and the tapered end I9 engages upon the shoulder 6 in the drill, the enlarged portion 28 of the head 22 will be in position midway of the bushing Il and the circulation of the flushing iiuid will be shut off. The pressure of the flushing fluid upon the upper end of the section 32 will be suillcient to force the upper end downwardly, carrying the head 22 therewith, compressing the spring 21`and moving the enlarged portion 28 of the head downwardly to open the passage'I2 thru the bushing II, and thus permitting the flushing uid within the section 32 of the core barrel topass out thru the openings 30 and from there thru the passage I2 to the lower end of the drill stem. 1 `The pressure of the ushing fluid will hold the upper end downwardly against the action of the spring 21 during the cutting of the core and the pressure of the flushing 'iluid will thus hold the core barrel I8 firmly in position within the core drill while the core is being taken. y A

When a sufficient sample has been obtained the drilling will be stopped and some means, such as the bushing I5', may be mounted upon the drill stem and employed to close the spacebetween the casing head and the drill stem. The connections with the pump may then be changed so as to force the flushing uid inwardly thru one of the inlet ports 40, and the upper end of the drill stem of the flus ng uid. The passage of the ushing fluid downwardly in the well will discharge upwardly thru the drill stem. The drill stem may be slightly raised to break off the core at the lower end andif necessary the-rdrill may be bumped of the hole to loosen the core and core barrel, so that the force of the flushing iluid will move the core barrel and the core upwardly thru the drill stem to the upper end. The full force of the pump may be exerted against the lower end of the core barrel and the core, due to the fact that the core barrel ilts fairly close within the passage thru the tool joints and one portion at least of the barrel will be extending thru one of the tool joints at all times. The core barrel upwardly thru the drill stem and discharged at the upper end for examination. When the core barrel has been thus removed the drill may proceed as before or the core barrel may be emptied and again pumped to the bottom of the hole ready for the taking of another core. When the circulation is reversedv the connections at the upper end of the well will. of course, have to be again changed to the usual and ordinary type of installation.

The advantages of clear from the description which has been given. 'I'he core barrel is adapted to receive the core in the same manner as with the usual core barrel. 'I'he duid, ii' any, which accumulates above the core while it is being taken, may pass upwardly past the valve 25 of the core barrel. Also it is to be noted that the driller will receive an indication of the arrival of 1 seat in the core drill. by

cut off when Vthe head choking the passage I2 continued circulation 22 arrives at its position, thru the bushing II. The of the flushing uid will above the core barrel and telescope 'the head wit the lower section thereof and the circulation will again proceed. When the driller thus notices that the core barrel is in and from thence tothe outside.

this construction will be u position he will be enabled to start rotating so vas to cut the core.

and from position in said drill bit.

When the core barrel is removed to the surface thru the force of the current of the flushing iiuid the pressure of the fluid below the core will assist in retaining the same within the core barrel and the sample will be discharged at the surface in thei same condition as it was at the bottom of the hole. I am thus enabledto obtain a sample of the 'formation Without removing the drill stem and without the wasting of any material amount of time in obtaining the sample. The device is adapted to be quickly inserted into position to take a. core and the core may be thereafter removed with very slight loss of time in the drilling of the well. No cables or latching means or other complicated apparatus are required in the operation of my device and there is very little wear upon the apparatus and little danger of damage to the drilling apparatus during the obtaining of the sample.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. In a core drill, a drill bit having a seat therein to receive a core barrel, a drill stem thereon having constrictedpassages therethru, in combination with a core barrel assembly adaptedto move freely in said drill stem from one end to the other thereof, and to fit upon said seat and to be moved in either direction in said drill stem by fluid pressure. -l

2. In a core drill, a drill bit having a seat therein to receive-a core barrel, a drill stem thereon in combination with a core barrel assembly adapted to move freely in said drill stem from one end to the other thereof, and to fit upon said seat and to lbe moved in either direction in said drill stem by fluid pressure. A y 3. In a core drill, a drill bit having a seat therein to receive a core barrel, a drill stem thereon, tool joints in said drill stem, in combination with a core barrel assembly adapted to move freely in said drill stem from one end to the other thereof, and to fit upon said seat and to be moved in either. direction in said drill stem by fluid pressure, said assembly being of a length equal to at least the distance between said tool joints.

4.V In a core drill, a drill bit having a seat, a drill stem thereon, a core barrel adapted to move longitudinally of said drill stem from one end to the other thereof and shaped to fit within a seat in said drill bit, and fluid pressure operated means to move said core barrel upwardly from said drill bit thru said drill stem.

5. In a core drill, a drill bit having a seat, a drill stem thereoma core barrel adapted to move longitudinally of said drill stem from one end to the other thereof and shaped to flt within the seat in said drill bit, a casing, and connections on said casing for circulation of fluid in'e'ither direction thru said drill stem to move said core barrel to 6. In a core drill, a drill bit having a seat, a drill stem thereon, a core barrel adapted to move longitudinally of said drill stem and shaped to fit within the seat in said drill bit, a casing through which fluid may circulate and thru 'said drill stem in either direction to move said core barrel to and from position in said drill bit, and means responsive to the circulation of said fluid to indicate when said core barrel has reached its seat in said drill bit. '1. In a c: re drill having a seat, a drill bit, a drill stem connected therewith, a core barrel adapted to move longitudinally in saiddrill stem and seat l in said drill, said drill stem being connected to circulate flushing iiuid to move said core barrel to said seat in said drill, and means to temporarily cut oif circulation of said flushing uid when said barrel is moved downwardly into contact with said seat.

8. IIn a core drill, a drill bithaving a seat, a drill stem connected therewith, a core barrel adapted to move longitudinally in said drill stem and seat in said drill bit, said drill stem being connected to circulate flushing fluid to move said core barrel to said seat in said drill bit, and means to temporarily cut off circulation of said flushing uid when said barrel is moved downwardly into contact with said seat, said circulation being .again opened thru the pumppressure upon said flushing fluid.

9. In a core drill, a core blt, a drill stein connected therewith, a core barrel movable freely in said drill stem, a seat for said barrel in said drill, said drill stem having a constricted passage above said drill, means on said core barrel engaging in said passage to close the same when said core barrel moves into said seat, said means being adapted to move to open said passage responsive tofluid pressure.

10. In a core drill, a core bit, a drill stem connected therewith, a core barrel movable freely in said drill stem, a seat for'said barrel in rsaid bit, said drill stem having a constricted passage above said drill, means on said core barrel engaging in said passage to close 4the samewhen said core barrel moves into said seat, a telescopic joint in said barrel below said means adapted to allow take a core and then causing a. reverse -liquid circulation to move said core barrel back to the surface with said'core.

12. In the recovery of cores from well drillsv the method of placing the drill upon the well bottom, causing the flight of the core barrelto said drill to receive the core, and causing a liquid circulation to return said core barrel to the surface. n

13. A core drill, a drill stem attached' thereto, a seat in said drill wlthinsaid drill stem, and a core barrel in said drill stem movable to and from the well surface tosaid seat by the circulation of liquid in said drill stem.

l'14. A core` drill, a drill stem atached thereto, said drill stem anddrill being arranged to permit the circulation of flushing uid in either direction, tool joints in said stem, a seat in said 4drill within said drill stem, and a core barrel in ment in either direction in said drill stem the full length thereof by the circulation of liquid in said drill stem, said circulation acting also to assist in the drilling of the well.

16. In a core drill, a drill stem adapted to rotatev while liquid is circulated therethrough. and a core-containing tube movable by fluid pressure in said drill stem to an'd from the lower and upper 'ends of said drill stem while said drill stem is beingrotated.

17. In a core drill, a tubular drill stem., a coring bit at itsllower end. and an inner tube slid- Vcore cutting means, a drill pipe, an inner core receiving tube, means for placing said inner core receiving tube in position for receiving core at the bottom of the well, said core-receiving tube being movable from the cutting means to the upper end of said pipe responsive to fluid circulation.

19. In a core drilling device for use in a well for retrieving core samples without removing drill pipe, an inner tube movable within the drill pipe from end to end thereof by slush circulation and while the drill pipe is being rotated;

20. In combination with a drill socket member, a drilling pipe extending upwardly therefrom, and a core cutting bit in the socket; of a core receiver adapted to be lowered through said pipe into said socket member and in register with the `bit, and means whereby the core receiver may be pumped up tothe top of the bore with the! core enclosed in-it.

21. In combination with a drill socket member,

va drilling pipe extending upwardly therefrom,

and a core cutting bit in the socket; of a core receiver adapted to be lowered through said pipe into said socket member and in register with the bit, and means whereby the core receiver may be pumped up to the top of the bore with the core enclosedin it, said means comprising aplunger fitting the drilling pipe above the receiver.

22. In combination with a drill socket member, a drilling pipe extending upwardly therefrom.

and a core cutting bit in the socket; of a core receiver adapted to be lowered through said pipe into said socket member and in register with the bit, and means whereby the core receiver may be pumped up to the top of the bore with the core enclosed in it, said means comprising a` plunger fitting the drilling pipe'fabove the receiver, and

means whereby said plunger will yield downwardly to pass water downwardly through the drilling pipe lto the socket member and bit.

23. A core drill, a core barrel adapted to t within said drill, a drill stem on said drill, said core barrel .shaped to move freely in said drill stem from end to end thereof and arranged to be moved by hydraulic pressure in both directions in said drill stem, and a seat in said drill to limit the downward movement of said barrel.

24. In a core drill a jointed drill stem having constrictions therein at said joints, an inner tube slidable longitudinally oi' said drill stem and through said constrictions the full length of said ydrill stem, the said inner tube being longer than the distance between said constrictions whereby fluid may act on said tube to move the same longitudinally of said drill stem.

25. In acore drill, a drill pipe, a drill bit thereon, and a core receiving tube within said pipe, said tube being'movable by fluid circulation .from said drill bit to the upper end of said drill the internal diameter` of said pipe sections, and

a bit secured to the lower end of said drill stem, o1 a core barrel movable downwardly in said drill stem and into a core receiving position adjacent said bit; means to hold said core barrel in said position; said core barrel being of `a length greater than the distance between said tool joints and o`f a diameter to snugly fit in said tool joints;

said core barrel having a core receiving chamber l and a uid chamber above and separated from said corereceiving chamber; `a port connecting said core receiving chamber and the interior of said drill stem at a point adjacent the upper end of said core receiving chamber; a relief valve in said port to permit'the escape of uid from said core receiving chamber into said drill stem and to prevent the entrance of fluid from said drill stem into said core receiving chamber; a

pair of vertically spaced ports connecting said uid chamber and the interior of said drill stem;

means to seal the space between said core barrel and said drill stem when said core barrel is in said position, at a point between said vertically spaced jports; and a uid valve in one of said vertically spaced ports to permit the passage of fluid from the interior Aof said drill stem above said core barrel through said bit and to prevent the passage of fluid from said bit to the interior of said drill stem above said core barrel; so that fluid may be pumped downwardly through said drill stem and bit during drilling operations, and said core barrel may be pumped upwardly through said drill stem.

28. The combination with a drill stem comprising pipe sections connected together by tool joints the internal diameter of which is less than the internal diameter of said pipe sections and a bit secured to the lower end of said drill stem, of a core barrel movable downwardly .in said drill stem and into a core receiving position adjacent said bit; means to hold said core barrel in'said position; said core barrel being of a length greater than the distance between said tool joints and of a diameter to snuglyiit in said tool joints; said core barrel having a core receiving chamber and a. fluid chamber above and separated from said core receiving chamber; a pair of vertically spaced ports connecting saiduid chamber and the interior of said drill stem; means to seal the space between said core barrel and said drill stem when said core barrel is in said position, at a point between said vertically spaced ports; and a uid valve in one of said vertically spaced ports to permit the passage of fluid from' the interior of said drill stem above said core barrel through said bit and to prevent the passage of fluid from said bit to the interior of said drill stem above said core barrel; so that iiuid may be pumped downwardly through said drill stem and bit during drilling operations and said core barrel may be pumped upwardly through said drill stem.

29. The combination with a drill stem and a bit secured to the lower end of said drill stem, of a core barrelmovable downwardly in said drill stemv ed from said core receiving chamber; a pairl of vertically spaced ports connecting said uid chamber and the interior of said drill stem;

means to seal the space between said core barrel prising pipe sections connected togeth; rby tool joints the internal diameter oi' which is less than and said drill stem when said core barrel is in said position, at a point between said vertically spaced ports; and a uid valve in one of said vertically spaced ports to permit the passage of fluid from the interior of said drill stem above said core barrel through said bit and to prevent the passage oi fluid from said bit to the interior of said drill stem above said core barrel; so that y wardly through4 said drill stem past said core barrel and to prevent the passage of fluid upwardly through said drill stem past said core barrel so that uid may be pumped downwardly through said drill, stem during drilling operations and said core barrel may be pumped upwardly through said drill stem..

31. 'I'he combination with a drill stem, of a core barrel movable downwardly in said drill stem into a core receiving position, and means to permit the passage of fluid downwardly through said drill stem past said core barrel and to prevent the passage of uid upwardly through said drill stem past said core barrel so that fluid may be pumped throughsaid drill stem during drilling operations and said. core barrel may be pumped upwardly through said drill stem.

32. The combination with drill stem.' of a corereceving instrument movable downwardly in said drill stem into a'core-receiving position and means to permit the passage of fluid downwardly through said drill stem past said instrument and Vto prevent the passage of fluid upwardly through said drill stem past said instrument so that fluid may be *pumped through said drill stern during drilling operations and said instrument may be pumped upwardly through said drill stem.

33A core taking apparatus including a tubular drill stem, a core barrel adapted to be supported in said stem for upward movement in the stem under upward pressure, means for introducing fluid under pressure through said stem, and means associated with the core barrel for interruptingthe iiow of uid upon said upward` movement of the core barrel.

34. In drilling wens by the rotary method, thel method of operation including lthe steps of introducing a core-receiving instrument into the upper end of the drill stem and moving it downwardly to operative position at the lower end of said drill stem by -fluid circulation, operating said drill stem to take a. sample into said instrument ofthe formation being drilled, and then reversing the fluid circulation and forcing said instrument with said core back through the drill stem to the surface.

35. In drilling wells by the rotary method, the

method of operation including the' steps of introducing la core-taking instrument into the upper end of the drill stem and causing said instrument to move downwardly to operative posi- 'tion at the lower end of said drill stem, operating to take into vsaid instrument a core of the formation being drilled, and then reversing the fluid circulation and employing said circulation tothe taking of an earth sample, which comprises pumping mud into the drill stem behind the core barrel to force the same into working position in the lower end of the stem, and pumping mud into the lower end of the stem from the outside of the latter and beneath the core barrel to eiiect the movement upwardly of the latter after an earth core has been taken thereby.

' 37. The herein' described method of core drilling wells which consists in feeding a cutting element into the formationbeing encountered so as to `define a core; feeding a core retainer in consonance with the advance of the cutting element to cause the newly formed core to be received within the core retainer; furnishing a circulating pressure uid to the immediate region of the cut being made to carry oil? the newly created cuttings and then upon congestion within the core retainer or the filling of the core retainer causing a substantial and noticeable variation in the pressure of such fluid so that the core drilling may be temporarily halted for the removal of the core retainer.

38. In well drilling apparatus including a tubular drill stem and bit, an earth core taking device comprising an elongated tubular body open at one end, a valve controlled opening at the other end of the body, said body being movable from the surface through the stem with the open end thereof disposed in the lower part of the tubular bit. plug means connected with the upper end vof the tubular body, and means facilitating the pumpingV of fluid into the stem beneath the plug means to effect raising of the tube to the surface.

39. In the recovery of cores from well drills, the method which comprises, causing the flight of the core barrel into the said drill to receive the core, and causing a liquid circulation toreturn said core barrel to the top of the well.

40. In a core drilling assembly, a drill stem, a drill bit thereon, a core barrel including a lower core receiving sectionto seat adjacent said bit,

an upper section mounted' thereon, and interfitting means in said drill stem and on said upper section to cut oi the flow of liquid through said stem when intertting, said upper section on said core barrel being movably mounted on said lower section to slide out of interfltting position whereby circulation is re-established.l y

4l. In a core drilling assembly, a drill stem, a drill bit thereon, a core barrel including a lower core receiving section to seat adjacent said bit, an upper section mounted thereon, interiittingmeans in said drill stem and on said upper section to cut oif the iiow of liquid through said stem when intertting, and said upper section on said core barrel being movably mounted on said lower section to slide outof interiitting position whereby circulation is re-establlshed, said upper section having a liquid passage therethrough.

42. In a core vdrill assembly including a drill stem, .a drill bit, al core barrel movable in said stem to seat adjacent said bit, a head on said core barrel, an area in said stem to receive said head, and spring means in said barrel supporting said head but yieldable to allow movement of said head to a position below said area in response to ,liquid pressure through said drill stem upon said head.

. HARRY PENNINGTON. 

